Copper vulcanization realizes selective carbon dioxide reduction to formate

Abstract

Herein, we demonstrate that the vulcanization of copper nanosheets (Cu₂S NSs) can realize selective electrochemical carbon dioxide reduction (CO₂RR) to formate (HCOOH). Results from experiments and in situ infrared spectroscopy reveal that Cu₂S NSs favor CO₂ reduction along the HCOO* pathway, leading to the selective formation of HCOOH. Impressively, the Faraday efficiency (FE) of HCOOH surpasses 70% in a broad potential range from −0.84 to −1.21 V versus (vs.) reversible hydrogen electrode (RHE), with a maximum value of 82%.